The benzoic acid benzene carboxylic acid
The benzoic acidrepresents powder or crystals from white till light-beige color badly soluble in water, it is good - in ethanol, chloroform and diethyl ether. Is weak elementary monobasic carboxylic acid of aromatic series.
It is easily sublimated - overtaken with water vapor therefore it is not necessary to concentrate water solutions of the benzoic acid evaporation.
Density is 1,32 g/cm ³-. Fusion point 122,4 ° - C, boiling point 249 ° - C, temperature of decomposition 370 ° - C.
Chemical formula: C7H6O2. - - - - the Certificate
The benzoic acid and its ethers contain in essential oils (for example in clove), toluansky and Peruvian balms, the benzoin resin.
Commercially the benzoic acid is received liquid-phase oxidation of toluene (methyl benzene) oxygen with the participation of the catalyst (naphthenate of manganese or cobalt). This process uses cheap raw materials and it is considered environmentally friendly. Also it can be received by hydrolysis of phenyl chloroform or cyanobenzene.
The benzoic acid and its salts possess the high bactericidal and bacteriostatic activity which is sharply increasing with reduction rn Wednesdays. Thanks to these properties, and also non-toxicity, the benzoic acid apply as food supplement E210 preservative in the food industry, mainly in brewing, in the confectionery and baking industry.
In medicine it is applied at skin diseases outwardly as antiseptic (antimicrobic) and fungicidal (antimycotic) means.
It is applied, along with the salts (benzoates) and ethers, in the cosmetic industry.
The benzoic acid - the most used chemical standard for determination of heat capacity of calorimeters.
Also it is applied as the accelerator of processes of polymerization and condensation when receiving synthetic rubbers and latex, in production of paints and varnishes, in the chemical, pulp-and-paper and textile industry - in production of fuels and lubricants, anti-icers, antifreezes.
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